hunter



fd toitrh grates gaunt @ffirr.

IMPROVEMENT'INTHH MANUFAGTURE 0P SODA AND POTASHP Qilge firtrtnlr rrfsrrrt lulu fijrse glitters also loit mrliing urt at figs same.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, A. G. HUNTER, of Flint, Wales, temporarily residing in Fair Haven, in the county of New Haven, and State of Connecticut, have invented anew Improvement in the Manufacture of Soda and Potash; and I do hereby declare the following to be a full, clear, and exact'desoription of the same. I

The object of my invention is to convert chloride of sodium (common salt) into silicate and carbonate of soda and caustic soda, and choride of potassium (muriate of potash) into silicate and carbonate of potash, and

caustic potash, with the production of mnria tic acid from the said chlorides. Ieffcct this by subjecting the chloride to be decomposed, to a heat snihcient to volatilize it, and causing the chleride vapor to act upon highlyheated silica in the presence of aqueous vapor, whereby a silicate of soda or silicate of potash and muriatic acid are produced.

The murial-ic acid is condensed and utilized for any of the purposes to which it is usually applied, and the silicate of soda or of potash under treatment is converted into a silicate soluble in water by fusing or boiling it with carbonate of soda or caustic soda, or with carbonate oi' potash or caustic potash, and the sbluble silicate of soda or of potash thereby produced is dissolved in water and converted into the corresponding carbonateby treatment with carbonic acid,,or into the correspondingcaustic alkali, by treatment with caustic lime, baryta, or magnesia. Several forms of apparatus may be employed to expose the silica. to the action of the alkaline chloride vapor. I now mention four, virv First. A stationary reverueratory furnace, on the hearth of which, nearest rue ore, is placed the chloride to be treated, and beyond it is placed the silica or silicious mineral to be acted on, steam being admitted to the furnace at the fireplace, so that the flame, heated steam, and chloride vapor all pas's together over and among the silicions mineralfthence through a condenser for the resulting muriatic acid, and thence to a chimney. The fused silicate of soda or of potash is allowed to flow out through anaperture in the furnace provided for this purpose.

Second. A revolving horizontal reverberatory furnace, in which the arrangement of materialsis similar to that just described in No. 1.

' Third. A vertical furnace, similar in construction to an iron-founder's cupola for melting iron, or to an iron smelters furnace for making pig-iron the fuel, chloride to be treated, and silicious mineral being sup plied from the top ofthe furnace, air and steam being admitted by tuyeres near the bottom of the furnace, the fused silicate flowing out at a suitable tap-hole near the bottom of the furnace and the muriatic acid conducted from theiurnace to acondcnscr. In employing this kind of furnace, the mnriatic acidmay be led oil either from a hood covering the top, or from an opening in the side of the furnace. In the latter case, the furnace-top should be closed, either by nmovable bell-shaped cover, or by enough depth of the materials to be furnaced above the muriatic acid outlet-flue, as to prevent the escape of vapors, as is ordinarily practised by iron-smelters who utilize the waste heat from their'hlagat-furnaccs for steam-boilers or air snperheaters.

Fourth. A stationary or revolving horizontal reverberatory furnace, or a. verticalcupola-furnace,.in which the chloride to be treate is volatilized, its vapor mixed with steam and the mixed gases, viz, the furnaceflame, chloride vapor, and s eam passed into a tower lined with fire-brick, and filled with the silicious mineral to' he acted on, the resulting silicate flowing down and odt at the bdttom of the tower, and the muriatic' acid led oil from the top of the tower to a condenser.

It is advantageons to cause the melted silicate produced in'any of these for s of furnace to how directly into another furnace, to be used with its corresponding caustic or carbonated a kalh'or to flow directly into a.

solution of its corresponding caustic or carbonated alkali, to be by either of these modes converted into a soluble silicatc of the alkali under-treatment. It is advantageous to use, (when they can he cheaply and readily obtainerb) silicious minerals containing silicate of the alkali whose chloride is to he treated, such ns' i'elspar or granite in the case of chloride of potassium. I

The proportions of materials are readily determined by practical chemists, from their chemical equivalents, and from the composition of the materials from time to time treated, care being taken at all times to present suihcient silica. to the chloride vapor, and suflicient caustic or carbonated alkali torender the resulting silicate soluble in water. The sil ca or silicate of lime, baryta, or magnesia precipitated from the soluble alkaline silicute is useful for glass-makers and potteries. The soluble alkaline silicate may be decomposed by injecting carbonic acid into an aqueous solution of the. silicate till the silica is precipitated, and the solution of carbonated alkali then run of from silica-and boiled to dryness, or the solution of alkaline silicate may be decomposed by caustic lime, beryta, or' niagnesia, the silicate of lime, baryta, or magnesia allowed to settle, and the solution of caustic alkali run oil and evaporated till sufiieiently concentrated to solidify when allowed to cool.

Having thus fully described my invention, what I claim as new and useful, and desire to secure by Letters Patent, is-- e 1 The process, substantially as herein described, of decomposing chloride of sodium and chloride of potassium, for the purpose of converting them into silicated, carbonated, or caustic alkali.

' I A. G'. HUNTER.

Witnesses:

Joan H. SnU wiY, A. J. Tnasr'rs 

